Steam jet bulking of multicomponent yarns for improved post textile processing

ABSTRACT

Processes for steam jet bulking of multicomponent yarns, yarns produced via these processes, packages of wound multicomponent yarns produced via these processes, and stretch fabrics and articles of manufacture of these yarns and stretch fabrics are provided.

FIELD OF THE INVENTION

This disclosure relates to a process for production of bulked multicomponent yarns and to products comprising multicomponent yarns produced from steam texturing in accordance with this process to obtain controlled stretch parameters in the processed yarn.

BACKGROUND OF THE INVENTION

Production of stretch fabrics having the stretch primary component be of non-spandex origin are desired for applications requiring durability and compatibility with certain textile processing methods.

Nonlimiting examples of fibers for these stretch fabrics include multicomponent yarns such as a bicomponent filament yarn containing PET and PTT polymers This conventional bicomponent yarn exhibits high shrinkage and retraction when heat is used to activate the differential polymer shrinkage to form permanent bulk. Fabric knitting and weaving processes with these yarns are challenging as this large change in yarn length reduction must be accommodated to maintain weight control and create a fabric with acceptable appearance and stretch. Unless the yarn is processed through an intermediate transformation step, the bicomponent yarn is limited to applications which support fabric designs which allow the self-bulking of the yarn to substantially reduce the length of the fiber upon exposure to heat. The direct introduction of the bicomponent yarn into package dying operations is inefficient due to potential crushing of the tube core and/or insufficient bulk developing under the wound condition when the reduction in length is restricted due to winding conditions. Additionally, it is difficult to get a level amount of color in the package dying process when high yarn shrinkage occurs. If the tube core is not crushed by high compression, yarn shrinking on the tube increases the package density to a point that the dye will not flow evenly through the package. This creates uneven relative dye amounts throughout the package resulting in rejects or barre if introduced into fabric.

Textile processing companies are aware of these challenges in package dying bicomponent yarns. Various complex equipment designs to address these challenges have been disclosed including drum relaxation such as disclosed in GB Patent 1198035. Methods such as skein dying with significantly reduced efficiencies and/or requiring non-traditional equipment to be obtained have also been disclosed

There is a need for alternative processed multicomponent yarns of non-spandex origin and methods for their production and use in stretch fabrics.

SUMMARY OF THE INVENTION

This disclosure is related to a process of using steam in a direct impingement method with high overfeed conditions to initiate bulking of multicomponent yarns including thermally activated elastomeric filament yarns. This pre-development of bulk through entanglement loop generation along with thermal coil generation allows these yarns to be processed in knitting or weaving textile processing equipment to provide improved control over stretch properties in the final fabrics. A combination of single component yarn and bicomponent yarn is also possible to reduce the number of yarns required in downstream processes and add control of the amount of elongation generated in the final yarn. The range of yarns that can be processed in this manner encompasses the entire range of normal apparel fiber (<600 dtex) and industrial applications (>200 dtex). The process allows plying of multiple ends of yarn increasing the dtex in the bulking operation to the final level desired with reduced number of feed yarn variants. The yarn can be wound onto cardboard tube or a plastic tube that will allow direct introduction into package dying equipment for fabric applications that require color in the yarn prior to the knitting or weaving of the yarns.

Accordingly, an aspect of this disclosure relates to a process for steam jet bulking of multicomponent yarns. In the process, a multicomponent yarn is overfed at high rates, for example, greater than 300 overfeed to upper limits in excess of 300%, into an entanglement jet using steam at a pressure of 10 psig or greater as the fluid media to provide partial thermal bulking and entanglement texturing of the multicomponent fiber.

In one nonlimiting embodiment, the resultant product is wound onto a cardboard or plastic tube to allow for direct processing into further textile processing equipment.

In some nonlimiting embodiments, heated water having a temperature above 60° C., in most embodiments between 70-100° C. is introduced prior to the entanglement jet.

In some nonlimiting embodiments, multiple feed yarns are plied at a point prior to the entanglement jet entrance.

Another aspect of this disclosure relates to a multicomponent yarn prepared from a process for steam jet bulking of multicomponent yarns wherein a multicomponent yarn is overfed at high rates into an entanglement jet using steam at a pressure greater than 10 psig as the fluid media to provide partial thermal bulking and entanglement texturing of the multicomponent fiber.

Another aspect of this disclosure relates to a package of the multicomponent yarn wound on either cardboard paper or plastic tube. In one nonlimiting embodiment, the wound multicomponent yarn package creates bulk through thermal activation that has a percent bulking efficiency (% BE) greater than 15%. In one nonlimiting embodiment, the wound multicomponent yarn package has a package weight greater than 1 kg.

Another aspect of this disclosure relates to a stretch fabric knit or woven from a multicomponent yarn prepared from a process for steam jet bulking of multicomponent yarns wherein a multicomponent yarn is overfed at high rates into an entanglement jet using steam at a pressure greater than 10 psig as the fluid media to provide partial thermal bulking and entanglement texturing of the multicomponent fiber.

Yet another aspect of this disclosure relates to an article of manufacture comprising a multicomponent yarn or stretch fabric of multicomponent yarn prepared from a process for steam jet bulking of multicomponent yarns wherein a multicomponent yarn is overfed at high rates into an entanglement jet using steam at a pressure greater than 10 psig as the fluid media to provide partial thermal bulking and entanglement texturing of the multicomponent fiber.

BRIEF DESCRIPTION OF THE FIGURE

FIG. 1 is a diagram outlining a nonlimiting embodiment of this disclosure for a steam texturing process for multicomponent yarns.

DETAILED DESCRIPTION OF THE INVENTION

This disclosure relates to a multicomponent direct spun fiber having the ability of one of the yarns to develop permanent bulk through differential shrinkage which is processed to develop bulk through direct high-pressure steam impingement of the fiber.

The process for steam jet bulking of multicomponent yarns of this disclosure comprises overfeeding multicomponent yarns at a high rate into an entanglement jet using steam as the fluid media and pressure to provide partial thermal bulking through thermal shrinkage and entanglement texturing of the multicomponent fiber.

Multicomponent yarns used in the process may comprise side by side bicomponent or eccentric sheath core bicomponent where the two components exhibit differential shrinkage when exposed to heat, and the shrinkage imparts a coiled structure to the yarn. It may be desirable to include one component of the yarn which is an elastomeric yarn in which the yarn length is reduced substantially through thermal shrinkage.

The components are a material choice and may include PET and PET where there is a viscosity difference between the two components, PTT and PTT where there is a viscosity difference between the two components, PIT and PET, PET and PBT, nylon and nylon where the two components have differing formulations or viscosity, other material selections known to those of skill in the art may also be used. In addition to the use of bicomponent yarns, single component yarns can be combined with bicomponent yarns to produce a combination yarn which can create special aesthetic appearances and simplify the number of yarn feeders in downstream knitting or weaving processes. An example is to combine a PET single partially oriented yarn along with a bicomponent PET/PTT yarn to tailor the desired stretch component content having a controlled stretch. A second example would be to combine a black PET fully drawn yarn along with a bicomponent PET/PTT yarn to create a heather effect.

For purposes of this disclosure, by “high rate” with respect to feeding or overfeeding of multicomponent yarn to an entanglement jet, it is meant at a rate of greater than 30% overfeed. Accordingly, in one nonlimiting embodiment of the present invention, the multicomponent yarn is overfed at a rate of greater than 30%.

In one nonlimiting embodiment, the process used to steam the multicomponent yarn for analysis is to lay the length of yarn onto a steam table and steam the sample for a minimum of 30 seconds in a relaxed condition.

The steam pressure used in the process may range from 10 psig up to 60 psig.

In some nonlimiting embodiments, the process further comprises winding the resultant product onto a cardboard or plastic tube to allow for direct processing of the bulked multicomponent yarn into further textile processing equipment.

In one nonlimiting embodiment, the process is aided by introduction of heated water prior to the introduction of steam to maximize the fiber temperature into the shrinkage range and increase entanglement efficiency. In one nonlimiting embodiment, the water is heated to temperature above 70° C.

In one nonlimiting embodiment, multiple feed yarns are plied at a point prior to entering the entanglement jet. This comingling of multiple plies increases the dtex of the feed. For example; if standard products produced used as feed yarns include 75 dtex, 150, dtex, 300 dtex, and a product of 450 dtex is desired, one end of 300 and one end of 150 dtex could be added together and plied prior to the introduction to the jet. Plying refers to running two or more ends into the same guide to allow them to run together as one yarn for the remainder of a process.

A nonlimiting embodiment of equipment which can be used in the process of this disclosure is depicted in FIG. 1. As shown in FIG. 1, stationary creel 1 holds the feed yarn packages and delivers the feed yarn to the overfeed roll. The feed yarn 2 can be fed as a single package or multiple plies can be comingled to increase the dtex of the feed. A driven overfeed roll 3 feeds the yarn from rates of 30% to 400% faster than the post jet speed. A heated water tank 5 with applicator 4 introduces heated water to the yarn. A steam supply 6 with regulator controls the steam pressure from 10 psig-60 psig. As shown in FIG. 1, the equipment further comprises a jet 7 suitable for entanglement such as an air texturing jet. Nonlimiting examples include ceramic or metal texturing jets or other entanglement jet designs. In addition, the equipment comprises a driven puller roll S and a standard windup 9 that can wind yarn at low tension onto a cardboard or plastic dye tube 10. It may be desired to overfeed multicomponent yarns at a high rate into an entanglement jet using steam as the fluid media and pressure to provide partial thermal bulking and steam bulking of the multicomponent fiber. In this embodiment, it may be desirable for the multicomponent yarn to be an elastomeric yarn in which the yarn length is reduced by 20% through thermal shrinkage.

As will be understood by the skilled artisan upon reading this disclosure however, the processing conditions and equipment used can be varied to control the final amount of bulk and stretch to match the desired stretch amount for applications that wish to maintain low to moderate stretch amounts while having excellent recovery properties. A wide range of overfeed and steam conditioning ranges can be used to vary the amount of potential bulk development to match the final intended product stretch requirements. Additionally, winding conditions can be varied to allow direct use or to be package dyed directly prior to use in textile fabric processing equipment.

This disclosure also relates to multicomponent yarn prepared from this process for steam jet bulking of multicomponent yarns as well as yarn packages, fabrics and articles of manufacture prepared from the yarn and fabrics.

The resultant multicomponent yarn prepared from this process contains a high amount of bulk with lower shrinkage which allows subsequent textile processing to be carried out without additional intermediate process steps. A key benefit is that larger weight packages can be wound onto plastic or cardboard paper dye tubes and be introduced into package dying equipment.

The wound multicomponent yarn package of this disclosure creates bulk through thermal activation that has a percent bulking efficiency (% BE) greater than 15%. The % BE is a significant factor determining whether the product will be able to be processed through a package dye process without excessive additional bulking and shrinkage occurring in the dying process to cause tube crushing or impact liquor flow to cause uneven dying. Success has been obtained when this value is 15% or higher. The % BE of products using a bicomponent PTT/PTT fully drawn feed yarn in the dtex range of 55 through 600 dtex has produced % BE in the range of 15 to 67%. Packages in this range have been successfully dyed in a package dying process. The % BE is used as a correlation factor to control the final elongation of the further processed yarn to tailor the product to a desired fabric stretch value.

In one nonlimiting embodiment, the package has a package weight greater than 1 kg. In one nonlimiting embodiment, the resultant product formed from the bulking operation weighs two kilograms or higher with a low density (low hardness).

Products produced by this process are useful in package dying for knitting and/or weaving processes and in direct knitting and/or weaving processes where it is desirable to have lower shrinkages through the finishing processes to control stretch properties and fabric weights, and/or to tailor the amount of stretch in the bulked fiber to obtain a target stretch characteristic in the finished fabric form. In one nonlimiting embodiment, the yarn produced by the process of this disclosure is used to knit or weave a stretch fabric. The final fabric garments are applicable to apparel end uses of shoes, socks, woven patterned shirts and shorts, and those requiring good fabric stretch and recovery using low temperature finishing processes to protect a companion fiber from heat damage. In one embodiment, the use of the yarn in shoe fabric uppers allows the use of a controlled stretch component with high recovery to eliminate the need for low melt yarns to lock down the excessive stretch when a spandex yarn is used as the stretch engine. The bulked yarn is also applicable to industrial application fabrics where the stretch component needs to be stable and not be of spandex form for durability.

All patents, patent applications, test procedures, priority documents, articles, publications, manuals, and other documents cited herein are fully incorporated by reference to the extent such disclosure is not inconsistent with this invention and for all jurisdictions in which such incorporation is permitted.

The following Test Methods and Examples demonstrate the present invention and its capability for use. The invention is capable of other and different embodiments, and its several details are capable of modifications and/or substitution in various apparent respects, without departing from the spirit and scope of the present invention. Accordingly, the Examples are to be regarded as illustrative in nature and non-limiting.

Test Methods Percent Bulking Efficiency (% BE)

To properly define the result of the process to provide bulk to the yarn and provide a test method that will allow quick test measurement method results, the following equation is used to describe the Percent Bulking Efficiency (% BE).

% BE=((SSLB−SSLF)/(ISL−SSLF))*100

-   -   Where:     -   ISL=Initial Sample Length Selected for all samples     -   SSLF=Steamed Shrinkage Length of Bicomponent Feed yarn     -   SSLB=Steamed Shrinkage Length of Bulked yarn

As an example, a test method would have a 50% Bulking Efficiency value under the following conditions:

-   -   ISL=36″     -   SSLF=9″     -   SSLB=22.5″

% BE=((22.5″−9″)/(36″−9″))*100=50%

EXAMPLES Example 1

A 165 dtex bicomponent PET/PTT fully drawn yarn produces a 2 kg. package size on a plastic dye tube having dimensions of 11.4″×3″. The % BE is 60%. The process conditions were established as follows:

Steam pressure of 28 psig

Feed speed at 360 ypm

Overfeed rate of 250%

Heberlein “A” series ceramic jet

Water fed from boiling water at 40 ml/min.

Example 2

A 167 dtex bicomponent of PET/PTT draw false twist textured yarn produces a 2 kg. package on a plastic dye tube having dimensions of 11.4″×3″. The % BE is 58%. The process conditions were established as follows:

-   -   Steam pressure of 35 psig     -   Feed speed at 530 ypm     -   Overfeed rate of 215%     -   Heberlein “A” series ceramic jet     -   Water fed from boiling water at 40 m/min

Example 3

Two ends of 165 dtex of PET/PTT fully drawn yarns were plied at the creel produces a 2.7 kg. package on a plastic dye tube having dimensions of 11.4″×3″. The % BE is 60%. The process conditions were established as follows:

-   -   Steam pressure of 32 psig     -   Feed speed at 398 ypm     -   Overfeed rate of 247%     -   Heberlein “A” series ceramic jet     -   Water fed from boiling water at 40 ml/min.

Example 4

A 165 dtex bicomponent of PET/PTT fully draw yarn produces a 2 kg. package on a plastic dye tube having dimensions of 11.4″×3″. The % BE is 19%. The process conditions were established as follows:

-   -   Steam pressure of 16 psig     -   Feed speed at 458 ypm     -   Overfeed rate of 55%     -   Heberlein “A” series ceramic jet     -   Water fed from boiling water at 40 m/min

Example 5

One end of 165 dtex bicomponent of PET/PTT fully drawn yarn is plied with two ends of 83 dtex PET fully drawn yarn to produce a 2 kg. package on a plastic dye tube having dimensions of 11.4″×3″. The % BE is 44%. The process conditions were established as follows:

-   -   Steam pressure of 36 psig     -   Feed speed at 482 ypm     -   Overfeed rate of 45%     -   Heberlein “A” series ceramic jet     -   Water fed from boiling water at 40 ml/min 

1. A process for steam jet bulking of multicomponent yarns, said process comprising overfeeding multicomponent yarns at a high rate into an entanglement jet using steam as the fluid media and pressure to provide partial thermal bulking and steam bulking of the multicomponent fiber.
 2. The process of claim 1 in which the entanglement jet is an air texturing jet.
 3. The process of claim 1 wherein the multicomponent yarns are overfed at a rate of greater than 30%.
 4. The process of claim 1 wherein the pressure is 10 to 60 psig.
 5. The process of claim 1 further comprising winding the resultant product onto a cardboard or plastic tube to allow for direct processing of the bulked multicomponent yarn into further textile processing equipment.
 6. The process of claim 1 further comprising introducing heated water to the multicomponent yarn prior to overfeeding the entanglement jet.
 7. The process of claim 6 wherein the water is heated to temperature above 70° C.
 8. The process of claim 1 wherein multiple feed yarns are plied at a point prior to entering the entanglement jet.
 9. A multicomponent yarn prepared from the process for steam jet bulking of multicomponent yarns of claim
 1. 10. A package of the multicomponent yarn of claim 9 wound on cardboard paper or plastic tube.
 11. The package of claim 10 wherein the wound multicomponent yarn package creates bulk through thermal activation that has a percent bulking efficiency (% BE) greater than 15%.
 12. The package of claim 10 having a package weight greater than 1 kg.
 13. A stretch fabric comprising the multicomponent yarn of claim
 9. 14. An article of manufacture comprising the multicomponent yarn of claim
 9. 15. An article of manufacture comprising the stretch fabric of claim
 13. 16. The package of claim 10 that has been dyed.
 17. A multicomponent yarn with a percent bulking efficiency (% BE) ranging from 15% to 67%. 